Conventionally, there are emergency brake devices in which an emergency stop or a speed governor is disposed on the counterweight side or which are provided with a rope brake that directly grips a main rope for cases where a car moves upwards at a speed higher than a rated speed due to a failure or accident in an elevator, due to an unbalance in weight between the elevator car and a counterweight, or the like.
Further, JP 5-193860 A discloses an emergency brake device having a braking bolt inserted between the spokes mounted to the shaft of the drive sheave.
Further, JP 6-199483 A discloses a brake device that stops a deflector sheave by pushing a wedge-like braking member between the sheave or the deflector sheave and the pressing member.
Further, JP 2002-241064 A discloses an emergency stop device in which wedge-like clamps are inserted on both sides of a car guide rail and braking is applied by sandwiching the guide rail from the both sides.
However, each of the conventional emergency brake devices as described above requires a space dedicated for the provision of the brake device and is rather complex in structure. Further, with the emergency brake device in which the braking bolt is inserted between the spokes, there is a time lag between the engagement of the braking bolt with the spokes and the generation of a braking force, so there is a problem in that the speed of the car increases during this time lag. Further, with the device in which the wedge-like braking member or clamp is inserted, no mechanism is provided for releasing the mechanical engagement of the inserted braking member or clamp to enable a restart. Further, with the device provided with the rope brake that directly grips the main rope or the device in which the guide rail is sandwiched from both sides, there is a problem in that damage is caused to the rope or the guide rail.
It is an object of the present invention to provide an emergency brake device for an elevator which does not require a dedicated installation space, is simple in structure, allows easy releasing of a braking force, and does not cause damage to a rope or guide rail of the elevator.